Statistical Analysis Plan (SAP)
What a definition is not
A definition is SPEQ’s plain-language decode of how a term is used in practice, cited to the documents that define it. It is a practitioner reference, not legal or regulatory advice, it does not replace the definition in the source, and where a regulator’s wording differs the regulator’s wording governs.
A document that elaborates the statistical section of the protocol into detailed, unambiguous procedures for the analysis of trial data, finalized and signed before database lock and unblinding. It specifies the analysis populations, methods for primary and secondary endpoints, handling of missing data, and any planned interim or subgroup analyses.
Where the protocol states what will be measured and the trial’s hypotheses, the SAP states precisely how the data will be analyzed — the statistical models, significance thresholds, and rules for every planned comparison, written before anyone sees unblinded results.
It defines the analysis populations, such as intention-to-treat, per-protocol, and safety populations, and specifies which one is primary for each endpoint, along with the method for handling missing data and any adjustment for multiple comparisons.
Finalizing the SAP before database lock and unblinding is what prevents data-driven, post-hoc analysis choices from silently biasing the reported result; any later deviation from the finalized plan must be disclosed and justified in the clinical study report.
- —Must be finalized and signed off before database lock and treatment unblinding to preserve analytical integrity.
- —Defines the analysis populations and which one is primary for each endpoint.
- —Specifies methods for handling missing data, multiplicity adjustment, and any planned interim or subgroup analyses.
- —Deviations from a finalized SAP must be justified and disclosed in the clinical study report.
ICH E9 Statistical Principles for Clinical Trials; ICH E9(R1) Addendum on Estimands and Sensitivity Analysis in Clinical Trials; ICH E3 Structure and Content of Clinical Study Reports
Frequently asked questions
What is Statistical Analysis Plan (SAP)?
A document that elaborates the statistical section of the protocol into detailed, unambiguous procedures for the analysis of trial data, finalized and signed before database lock and unblinding. It specifies the analysis populations, methods for primary and secondary endpoints, handling of missing data, and any planned interim or subgroup analyses.
Which regulations cover Statistical Analysis Plan (SAP)?
ICH E9 Statistical Principles for Clinical Trials; ICH E9(R1) Addendum on Estimands and Sensitivity Analysis in Clinical Trials; ICH E3 Structure and Content of Clinical Study Reports